Weldability Sif has launched Sifbronze ECO paste flux, a boric-acid free solution that can be applied directly to the weld joint or as a ‘deep dip’ to the filler rod to aid cleaning and consumable flow when oxy/acetylene brazing and for other welding applications on mild steel, copper alloys and cast iron.

A feature of this patented paste flux is that it is ecologically clean in that it does not contain traditional noxious ingredients normally associated with brazing fluxes and meets the European Union REACH Registration, Evaluation, Authorisation and restriction of Chemicals regulations introduced in June 2007. These regulations are designed to provide a high level of protection of human health and the environment from the use of chemicals as well as make the people who place chemicals on the market, both manufacturers and importers, responsible for understanding and managing the risks associated with their use.

Other features of this paste flux are that it can be used in a wide range of applications and it can be used by itself, where 3 fluxes would have been used in the past.

This pre-mixed flux paste, which has a melting point starting from 420°C, can be either applied directly to the weld joint and because it is supplied in a 124mm deep jar, it can be used as a deep dip to fully coat the filler rod, making it an economic product to use.

It can be used with multi-purpose Sifbronze No.1 and Sifbronze No. 101 brazing rods on mild steel and copper alloys. It can also be used on copper welding applications with SifsilCopper No 7 brazing rods for full fusion welding of de-oxidised copper sheet as well as in cast iron welding applications with Sif Super Silicon No. 9 brazing rods, which produce easy to machine, high strength welds.